Impressions on RT
First of all, it's not for the faint of heart. First daunting task is fulfilling its "myriad dependencies"; i kid you not, these number in the tens of perl modules needed to run the thing. While the included script uses the CPAN module to automate most tasks, some of them might fail and it takes a bit of intervention to finish installing required modules; in my case, it was unable to instal HTML::Mason (and it's quite an important dependency) so I had to install it by hand.
Next, you're left to wrestle with mod_perl, which is a pretty hairy beast by itself. On a Red Hat 7.2 box, mod_perl is installed as a DSO loadable module, and, as RT's documentation states, this configuration is not advisable; indeed, apache simply crashed when rt's configuration was present in httpd.conf. RT's recommendation is to compile mod_perl statically, again, a task not fit for beginners as it entails downloading and compiling apache and mod_perl from source.
I ended up ditching mod_perl and going the mod_fastcgi route, which worked fine and voila, there was my functional RT installation.
Once RT is working, you'll be faced with a system that's so versatile, it can be intimidating. It's well thought-out, and has plenty of options, but could be a bit overkill for many needs.
However, anyone brave enough to face the daunting installation process, and patient enough to learn all the intricacies this system has, will be rewarded with a jaw-droppingly impressive tool for request management. Once I finished the installation and played with the system a little, I demoed to the staff here and they were all awed at how RT keeps track of *everything* and lets us use all that accumulated knowledge to solve problems easier and faster, and most important, with a degree of accountability we'd only dreamed of.
Highly recommended, assuming you have a competent geek available for installation.
qmail by itself is a great piece of software. It gets the job done, and gets it done in a quick, efficient and safe way. Based purely on its technical merits, it's hard to beat qmail for the one task it performs (being a mail transfer agent).
Unfortunately, qmail is not perfect, and most of its flaws come from the author, D.J. Bernstein.
The first thing that strikes a newcomer to the qmail community is how much like a god DJB feels. He's arrogant, somewhat disrespectful, and in general acts like he's the only human being in the world who knows what he's doing.
A lot of qmail's power comes from the fact that it breaks away with most conventions about MTA's, however that also means that most users will take some time to get used to how qmail operates. Here, DJB's "that's the way I did it and if you don't like it you can kiss my ass" attitude doesn't help one bit.
Also, plenty of issue has been made about qmail's license. It's not free in the FSF sense of the word, because you're not allowed to distribute modified versions of qmail. Of course you can make modifications, but you're limited to distributing those as patches, further increasing the difficulty level for a qmail installation. DJB maintains control of qmail's official release, which allows him to keep things working the way he wants to, but that means a lot of people can't share *their* way of doing things unless DJB approves.
If you can get over DJB's nastiness, and qmail's non-freeness doesn't bother you, qmail is really worth a try. Unfortunately bor both the author and his software, those are two pretty big IFs.